Single lobe washing machine pump



Oct. 10, 19.61

H. F. PRASSE V'SIIIG-L'E LOBE WASHING MACHINE PUMP Filed Sept. l0, 1957 2 Sheets-Sheet l M @ZW Wm'ff mg Oct. 10, 1961 H. F. PRAssE 3,003,424

SINGLE LOBE WASHING MACHINE PUMP Filed Sept. l0, 1957 2 Shee'bs-Sheerl 2 United States Pate 3,003,424 SINGLE LOBE WASHING MACHINE PUlVIP Herbert F. Prasse, Gates Mills, Ohio, assigner tc Thompson Ramo Wooldridge Inc., a corporation of Ohio Filed Sept. 10, 1957, Ser. No. 683,123

' 8 Claims. (Cl. 10S-83) This invention relates generally to pumps and more particularly to improvements in a single lobe-bl-aded impeller pump capable -of pumping both -gaseous and liquid fluid as may be required in use With washing machines and the like, although other uses and purposes of the invention will be apparent to one skilled in the art.

In pumps of the type disclosed herein, the porting plug is subjected toexpanding action due to moisture absorption and high temperature operation of the pump. In accordance with the principles of the present invention, a lporting plug is restrained from expanding excessively by providing bushings which are pressed on the outside diameter of the plug rather than into the inside diameter of the impeller, thereby restraining the plug from growing excessively.

Moreover, in pumps of the Itype disclosed herein utilized in an environment such las that provided by a laundry machine, foreign particles such as lint are frequently carried in the pumping medium and accumulations are likely to build up in the clearance spaces. In accordance with the principles of the present invention, the impeller is provided with water circulating means such as venting passages, thereby permitting some water to .circulate in the clearance spaces between the ends of the impeller and the bearing cap and housing and preventing the build-up of lint or foreign particles in the clearance spaces.

Itis an object of the present invention, therefore, to provide an improved pumping device which overcomes the deficiencies of the prior art.

Another object of the present invention is to provide a 'single lobe pump of the liquid ring-type wherein means are provided to prevent excessive expansion of the porting plug due to moisture absorption and high temperature operation of the pump.

Yet another object of the present invention is to provide a liquid ring-type pump having means to prevent build-up of foreign particles in the clearance spaces within the interior of the pump.

Still another object of this invention is to provide A further object of this invention is to provide a pump v of the stated type which is characterized by ease of manufacture and facility of operation, and wherein eiective means are provided. for journalling the 'annular impeller while at the same time constrainingthe port plug to prevent swelling due absorption.

vA still further object of vthis invention is to provide a pump of theA character described wherein the principal elements are formed of a suitable plastic such as` polystyrene or the like and in whichthe operative elements are s'o-arran'gedl as substantially toreduce friction losses.

Another object of the invention is tot'provide a pump vofthe stated type particularly suitable Afor Ause Washing machines -in which the ends. of the annular impeller to heating or moisture relatively low noise level due to the elimination ofthe usual double lobe, double port arrangement which results in the formation of wave fronts due to impulses from two exhaust ports meeting in a single outlet pipe.

Other objects, features and advantages of the invention will be apparent from the following detailed description, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals refer to like parts, and in which:

On the drawings:

FIGURE 1 is an end elevational view of a pump constructed in accordance with the principles of the present invention;

FIGURE 2 is a cross-sectional view with parts in elevation, taken substantially along line II-II of FIG- URE l, and with certain parts omitted for the sake of clarity;

FIGURE 3 is a transverse sectional viewl taken substantially along line IIL-III of FIGURE 2;

FIGURE 4 is a fragmentary and broken axial sectional view taken in FIGURE l, with some parts in elevation, and taken substantially along the lines IV-eIV;

FIGURE 5 is a fragmentary end elevational View of the drive shaft end of the pump.

As shown on the drawings:

Referring particularly to FIGURES 2 and 4, the pump of the instant invention comprises a pump of the liquid ring type and includes generally a pump housing 10, a pump co-ver member 11, an impeller 12, a porting plug 13, and a drive shaft 14.

The pump housing, cover member, impeller `and porting plug are molded or cast from a thermoplastic or thermosetting synthetic resin, such as polystyrene,` resistant to water carried detergents, capable of withstanding temperatures elevated to 200 F. without distortion, and easily shaped and fabricated as pump 'cornponents within the limits of operating tolerances without requiring machining.

The housing 10 includes a main body portion 15 of generally cylindrical shape within which is formed a pumping chamber 16 including a portion referred to herein as a single lobe displacement chamber 16a most clearly shown in FIGURE 3. The chamber 16a as illustrated, is preferably formed by positioning the impeller in an eccentric position with respect to the pumping chamber'16. This forms in effect a lobe at one side of the chamber 16. The chamber 16a is a lobe with respect to the portion of the chamber 16 occupied by the impeller 12 so that this pumping chamber may be herein referred to as a single lobe chamber.

At one end of the casing or housing 10, there is provided an end Wall 18 terminating in a reduced tubular extension 19 provided with a bore 20. A counterbore 20d is formed between the pumping chamber 16 and the bore 20; v v

At the opposite end of the casing or housing 10, there is provided a flange 17 to which isv attached the cover member 11, a plurality of suitable fasteners being indicated at 29. jf

'I'he cover member 11 has a tubular extension llaprovided'with a bore 26 and is progressively counterbored Y as at 25, 24 and 23, there being radially extending shoulare spaced` from the pump housing to reducefn'ctional losses and in which means'are provided for introducing pressure fluid into the spaces thus formed to remove accumulations of lint.

Another object of the invention is to provide a liquid ring pump whichis characterized by operation at a ders provided between each adjacent pair of counterbores.

`The impeller of the present invention, as indicated generally at 12, comprises an annular row of circumferentially spaced vanes or blades 30-which are integrally joined at their opposite sides to a pair of axially spaced annular end plates 31 and 32. The vanes 30 are tapered from the outer radial edge to the inner radial edge to form 0 passageways 33 between the vanes of subst-antially uniularly characterized by the provision of two bushings 52 and 54, respectively, which are pressed or molded on the outside diameter of the porting plug 13. The bushings 52 and 54 constitute rings or sleeves which restrain the plastic porting plug 13 from expanding excessively due to moisture absorption or high temperature operation of the pump. It will be noted that the'bushings 52 and 54 are pressed on the outer diameter of the porting plug 13 rather than into the inside diameter of the impeller 12. Such .arrangement accomplishes the restraint in growth desired in accordance with the principles of the present invention since the bushings 52 and 54 act as bands to restrain the porting plug 13 from growing excessively.

The bushings 52 and 54 develop an additional function in that the bushing 52 has a bearing surface 52a and the bushing 54 has a bearing surface 54a. The bearing surfaces 52a and 54a are spaced apart from one another longitudinally vand provide a journal and bearing support for rotatably supporting the impeller 12 on confronting bearing surfaces 52b and 5417 provided at longitudinally spaced points within a center bore 12a extending longitudinally through the interior of the impeller 12.

As shown in the drawings, the end plate 31 of the impeller 12 is spaced from the adjoining surface of the end wall 18 thereby leaving a clearance space indicated at Z. Likewise, the end plate 32 is spaced from the adjoining surface of the cover member 11 to provide a clearance space indicated at Y.

In accordance with the principles of the present invention, the end Wall 31 is provided with an axially extending aperture or venting opening 31a and the end wall 32 is likewise formed with an axially extending opening or venting aperture 32d. Some of the fluid being pumped is thus permitted to circulate in the clearance spaces Y and Z between the ends of the impeller 12 and the bearing cap and housing formed by the housing 10, the end wall 18 and the cover member 11. Such circulation prevents lint or other foreign particles from building up in the clearance spaces Y and Z and considerably enhances the satisfactory operation of the pump. As will be appreciated, the pressure in the clearancespaces Y and Z will always be somewhere between the inlet and outlet pressure of the pump inasmuch as there is slight communication between the clearance spaces Y and Z and the passageways 33 between the vanes of the rotor over the outer peripheral edges of the annular end plates 31 and 32 and some of the passages are at inlet pressure and others are at outlet pressure. When the passageway 33 which is exposed to the venting openings 31a and 32d is at inlet pressure uid flows from the clearance spaces Y and Z into said passageway 33. When the same passageway is at outlet pressure tiuid ows out through the openings 31a and 32d into the annular spaces Y and Z.

The casing or housing is formed with an inlet 21 and an outlet 22. To divide the fluid ow therebetween, the porting plug 13 includes an elongated plate-shaped main body 39 extending Vsubstantially diametrically across the cylindrically reduced casing section and the central bore 12a of the impeller and longitudinally from the end of the casing or housing 10 to the opposite end of the impeller 12.

In operation, fluid enters the intake port 21, ows into the intake zone at one sidey of the porting plug 13, is drawn into the passages 33 of the vanes 30, and is impelled radially outwardly into the lobe 16a. The iluid is forced through adjacent vane passages from the lobe 16a to the outlet zone on the other side of the plug 13 and ows outwardly through the outlet 22.

To rotatably drive the impeller y12, the drive shaft 14 is rotatably journaled on bearing surfaces indicated at 35 received in the bore 26 of the tubular extension on the cover member 11. A shaft seal is provided as at 36 and a pilot portion 14a on the end ofthe drive shaft 14 projects Vinto a recess formed in one end of the porting plug 13. A splined driving connection is effected between the impeller 12 and the drive shaft 14 by cooperating external splines 34b and internal splines 34a.

Although minor modifications might be suggested it should be understood that I wish to embody all such modifications as are reasonable and proper within the scope of the patent warranted thereon.

I claim as my invention:

1. A pump including a housing having an inlet and an outlet, a drive shaft bearingly supported by said housing, an impeller in said housing drivingly connected to said shaft, said impeller being diametrically smaller than the inner housing wall and eccentrically mounted with respect to said housing, an axial bore through said impeller communicating through the periphery of the impeller with the interior of the housing and coaxial with the axis of rotation of the impeller, a porting plug fixed in said housing and extending axially into said bore made of a material subject to expansion due to moisture absorption at high temperature operation of the pump and having a portion extending across the bore dividing the impeller bore into an inlet zone and outlet zone, means connecting said zones respectively with said inlet and said outlet, and a pair of axially spaced bushings non-rotatably mounted on said porting plug made of ya material of suicient stability to prevent swelling of said porting plug and forming bearing surfaces journalling said impeller.

2. A pump including a substantially cylindrical housing having an inlet and an outlet, an annular impeller rotatably ycarried in said housing in eccentric relation thereto, a drive shaft connected to said impeller, an axial bore into the impeller communicating with the impeller and the periphery of said impeller and coaxial with the impeller axis, and a stationary porting plug fixed in said housing extending into the bore of said impeller and having a portion extending across the bore and coacting with surrounding impeller structure to form passages communicating an arcuate portion of said impeller bore with said inlet and a diametrically opposed arcuate portion of said bore to said outlet, said porting plug being made of a material subject to expansion due to moisture absorption rand high temperature operation of the pump and being provided with bushing means nonrotatably located on the plug and made of a material having sufficient stability for constraining swelling thereof and forming 'bearing members journalling said impeller.

3. A pump including a substantially cylindrical housing having an intake port and an outlet port, an annular impeller rotatably carried in said housing in eccentric relation to the inner housing walls, a drive shaftconnected to said impeller, a bore in the impeller communicating through the periphery-of the impeller with the interior of the housing and coaxial therewith, and a stationary porting plug xed in said housing extending into said bore coacting with surrounding impeller structure to form passages intercommunicating a first arcuate portion of said impeller bore and said intake port and a second arcuate portion of said impeller bore and said outlet port, said second arcuate portion being substantially diametrically opposed with respect to said rst arcuate portion, said porting plug being made of a material subject to expansion due to moisture absorption and yhigh temperature operation o'f the pump andv provided on the outside diameter thereof with a pair of axially spaced metal bushings non-rotatably mounted on the plug Aconstraining swelling of said porting plug due to moisture absorption or a rise in temperature and forming bearing surfaces journalling said impeller.

4. A pump including 4a housing having an inlet and an outlet, a pumping chamber in said housing, an annular impeller lrotatably mounted in said chamber and cooperating therewith to form a single lobe, a drive shaft connected to said impeller, a bore coaxial with the impeller axis and communicating through the impeller at the periphery thereof with the pumping chamber, a porting plug fixed in said housing'extending axially into the impeller bore and having a portion extending across the bore dividing the impeller bore into an inlet zone and an outlet zone, means connecting said zones respectively to said inlet and said outlet, said porting plug being made of `a material subject to expansion due to moisture absorption and high temperature operation of the pumps, means for supporting the porting plug in the housing, and a pair of axially spaced metal bushings mounted non-rotatably on the outside diameter of said plug constraining swelling of said porting plug.

5. A pump including a housing having an inlet and an outlet, a pumping chamber in said housing, an annular impeller rotatably mounted in said chamber and cooperating therewith to form a single lobe, a drive shaft connected to said impeller, said impeller having annular end plates spaced from said housing forming a pair of annular chambers, vent means in each of said end plates for circulating working fluid between the impeller and said annular chambers, a bore in said impeller communieating through the periphery of the impeller with the pumping chamber and coaxial with the axis of rotation of the impeller, means supported in the housing extending across said impeller bore dividing said bore into inlet and outlet zones in circumferentially displaced locations, and means connecting said zones respectively to the inlet and outlet of said housing.

6. A pump including a housing having an inlet and an outlet, a pumping chamber in said housing, an annular impeller rotatably mounted in said chamber and eccentn'cally positioned with respect to an axial center line extending through said chamber thereby forming with the Walls of said chamber a single lobe pumping space, said impeller having annular end plates spaced from said housing thus forming a pair of annular chambers, venting means in said end plates forming openings for circulating working fluid between the impeller and said annular chambers, a drive shaft connected to said impeller, a bore in the impeller coaxial with the impeller axis and communicating through the periphery of the impeller with the pumping chamber, and a porting plug supported in the housing extending axially into said impeller bore and dividing the bore into an inlet zone and an outlet zone connected respectively to the inlet and the outlet of said housing.

7. A pump including a housing having an inlet and an outlet and having an annular outer wall and end walls, a pumping chamber in said housing, an annular impeller rotatably mounted in said chamber and eccentrically positioned with respect to the axial center of said chamber thereby forming with the walls of said chamber a single lobe pumping space, said impeller having end plates in spaced relation to adjoining end walls of said housing thus forming a pair of annular chambers, a vent opening means in each 0f said end plates for circulating working fluid between the impeller and said annular chambers, a drive shaft connected to said impeller, a bore in the impeller coaxial With the impeller axis and communicating through the periphery of the impeller with the pumping chamber, a iixed porting plug supported in the housing extending axially into said impeller bore and dividing the bore into an inlet zone and an outlet zone, and means connecting said zones to communicate respectively with the inlet and the outlet of said housing.

8. A pump including a housing having an inlet and an youtlet and having an annular outer wall and end walls, a pumping chamber in said housing, an annular impeller rotatably mounted in said chamber and eccentrically positioned with respect to an axial center extending through said chamber thereby yforming with the walls of said chamber a single lobe pumping space, said impeller having annular end plates in spaced relation to adjoining end walls of said housing thus forming a pair of annular chambers, each of said end plates being provided with a vent opening means alfording circulation of fluid between the impeller and said annular chambers, a bore in the impeller coaxial with the impeller axis of rotation and communicating through the periphery of the impeller with the pumping chamber, a porting plug supported in the housing extending axially into said impeller bore and dividing the bore into an inlet Zone and an outlet zone, means connecting said zones to communicate respectively with the inlet and outlet of said pump, and a pair of axially spaced bushings on the outside diameter of said plug constraining swelling thereof and journalling opposite ends of said impeller.

References Cited in the iile of this patent UNITED STATES PATENTS 1,611,265 Carrey Dec. 21, 1926 2,025,959 Seibold et al. Dec. 31, 1935 2,098,244 Hopfensberger Nov. 9, 1937 2,201,575 Corneil et al May 21, 1940 2,364,370 Jennings Dec. 5, 1944 2,629,540 Beck Feb. 7A, 1953 2,808,783 Geldhof Oct. 8, 1957 2,836,877 Hannahan June 3, 1958 2,846,979 Kumm Aug. 12, 1958 FOREIGN PATENTS 648,731 Germany Aug. 7, 1937 734,587 Germany Apr. 19, 1943 

